The CNS Flashcards
The nervous system consists of?
CNS:Brain and spinal cord
PNS: Cranial and spinal nerves (sensory and motor neurons)
Ganglia (nervous tissue containing neurons
Sensory receptors (either part of neurons or specialised cells that monitor changes in environment
Enteric plexus (regulate the digestive system
Three basic functions of the nervous system are?
Sensory function through receptors
Integrative function - analyses the sensory data store some of it and make decisions for it
Motor function - respond to stimuli by initiating action
What three systems does the PNS split into
Autonomous nervous system
Somatic nervous system
And enteric nervous system (digestive system)
What three systems does the PNS split into
Autonomous nervous system
Somatic nervous system
And enteric nervous system (digestive system)
Describe the spinal cord structure
Begins at the medulla oblongatta and stops at second lumbar vertebra
31 pairs of spinal nerves
Spinal cord what is it protected by?
Vertebrae
Two connective tissue coverings (meninges and vertebral column)
Cushion of cerebrospinal fluid
Describe internal structure of spinal cord
Spinal cord divided into grey and white matter
Grey matter comprises: cell bodies of motor neurons association neurons and unmyelinated axons of afferent neurons
White matter consists of bundles of myelinated axons of motor and sensory neurons
Input and output roots in spinal cord
Dorsal root: sensory nerve fibers send impulses into spinal cord PNS
Ventral root: motor neuron axons conduct impulses out to periphery
Sensory fibres enter through the dorsal horn and terminate in specific sites
Sensory fibres ascend to the brain via white matter Grey matter
What is white matter divided into?
White matter is divided into tracts with each column containing bundles of axons that carry similar info and go similar places
Sensory tracts go up to brain and motor tracts go down the cord
Spinothalamic means spinal cord to thalamus
Corticospinal means cortex to spinal cord
Brain protected by cranial meninges and cranial bones
What are the principal parts of the brain?
Brain stem
Diencephalon
Cerebrum
Cerebellum
Brain stem consists of?
Most cranial nerves originate from Brain stem
Primitive region involved in basic needs such as sleeping breathing autonomic
Cerebrum is the largest part of brain, what does it consist of
Cerebral cortex is composed of grey matter
White matter contains tracts that connect to other NSs
